biology Enlish(3)

The use of biofuels reduces dependence on petroleum and enhances energy

[4]security. Also, unlike fossil fuels, which return carbon that was stored

beneath the surface for millions of years into the atmosphere, biofuels can produce energy without causing a net increase of atmospheric carbon. This is because as new plants are grown to produce fuel, they remove the same amount of carbon dioxide from the atmosphere as they will release as fuel. However, some studies have found that certain crops may produce more harmful greenhouse gases than carbon dioxide, indicating that the specific biofuel used is an important factor.

Historical highlights

Humans have used solid biofuels (such as wood and other biomass) for heating and cooking since the discovery of fire. Following the development of ways to produce electricity, it became possible to use biofuels to generate electrical power as well. However, the fluctuations of supply and demand, energy policy, military conflict, and the environmental impacts, have all contributed to a highly complex and volatile market for energy and fuel. For example, the discovery of large supplies of fossil fuels—coal, natural gas, and oil—led to dramatic reductions in the use of biomass fuel in the developed world for transport, heat, and power. Petroleum-based fuels became inexpensive and soon were widely used to operate cars and trucks.

Before World War II, and during the high-demand wartime period, biofuels were valued as a strategic alternative to imported oil. Wartime Germany experienced extreme oil shortages and pursued many energy innovations, including the powering of some vehicles using a blend of gasoline with alcohol fermented from potatoes, called Monopolin. In Britain, grain alcohol was blended with petrol by the Distillers Company Limited under the name Discol.

After the war, inexpensive oil from the Middle East contributed in part to the lessened economic and geopolitical interest in biofuels. Then, in 1973 and 1979, geopolitical conflict in the Middle East caused OPEC to cut exports, and non-OPEC nations experienced a very large decrease in oil supply. This "energy crisis" resulted in severe shortages, and a sharp increase in the prices of oil-based products, notably gasoline. There was also increased interest from governments and academics in energy issues and biofuels.

Since the year 2000, there has been renewed interest in biofuels. The drivers for biofuel research and development include rising oil prices,